On Tuesday 13 January 1818, Keats wrote to his brothers George and Tom:
“I do believe — not speaking with any poor vanity — that works of genius are the first things in the world.”
On Monday 12 January 1818, Keats saw Richard III at Drury Lane. He wrote to his brothers:
‘I made an appointment with Wells to go to a private theatre, and it being in the neighbourhood of Drury Lane, and thinking we might be fatigued with sitting the whole evening in one dirty hole, I got the Drury Lane ticket, and therewith we divided the evening with a spice of Richard III.’ 
[The private theatre] ‘was of the lowest order, all greasy and oily, insomuch that if they had lived in olden times, when signs were hung over the doors, the only appropriate one for that oily place would have been — a guttered Candle. They played John Bull, The Review, and it was to conclude with Bombastes Furioso — I saw from a Box the first Act of John Bull, then went to Drury and did not return till it was over — when by Wells’s interest we got behind the scenes — there was not a yard wide all the way round for actors, scene-shifters, and interlopers to move in — for ‘Nota Bene’ the Green Room was under the stage, and there was I threatened over and over again to be turned out by the oily scene-shifters. 
[1 Letter to to George and Tom Keats 13 January 1818]
[2 Letter to to George and Tom Keats 23 February 1818]
On Sunday 10 January 1818, Keats wrote to the painter Benjamin Robert Haydon:
‘I am convinced that there are three things to rejoice at in this Age — The Excursion, Your Pictures, and Hazlitt’s depth of Taste.’
On Monday 5 January 1818 Keats wrote to his brothers:
“This day I promised to dine with Wordsworth, and the Weather is so bad that I am undecided for he lives at Mortimer Street. I had an invitation to meet him at Kingstons’s — but not liking that place I sent my excuse — What I am thinking of doing to day is to dine in Mortimer Street (Wordsth) and sup here in Feathersne Buildg as Mr Wells has invited me. On Saturday I called on Wordsworth before he went to Kingston’s and was surprised to find him with a stiff collar. I saw his Spouse and I think his Daughter.”
We know that he carried out his plan: on 10 January 1818 he wrote to his publisher John Taylor:
“I have seen Wordsworth frequently — dined with him last Monday.”
On Sunday 4 January 1818, Charles Wells and Joseph Severn dined with Keats.
“We had a very pleasant day. I pitched upon another bottle of claret — Port — we enjoyed ourselves very much were all very witty and full of Rhyme — we played a Concert from 4 o’clock till 10.”
Charles Wells was a school-friend of Keats’s brother Tom (who would later torment Tom by sending fake love-letters purporting to be from ‘Amena’).
Joseph Severn would be Keats’s final companion in Rome in 1821.
The ‘Concert’ was one in which each of the inebriated guests imitated an instrument of the orchestra. Keats usually took the bassoon part. It was almost certainly more fun for those taking part than for anyone who had to hear it.
On Saturday 3 January 1818, Keats called on Wordsworth, who kept him waiting, and then couldn’t see him as he was off to a meeting. Keats went on to party given by George Reddell at which they discussed the derivation of bawdy slang words.