John Bishop has been battling against the choppy waters of the English Channel and extreme fatigue as he tackled the second stage of his mammoth triathlon - a 26-mile row.
The funnyman - whose Paris to London trek also involves cycling and running - was joined by Davina McCall, Denise Lewis and Freddie Flintoff as rowers for the Channel crossing.
The quartet carved their way through two and a half miles in the first hour on the water after setting off from Calais this morning.
Bishop was nursing aches and pains from a 185-mile cycle ride and intense sleep deprivation with just an hour's sleep before boarding the boat. The saddle-sore star had muscle damage and severe bruising on his bottom from the punishing pedalling.
He said: "I massively underestimated how tough the cycle would be - there were 10 hours yesterday when I didn't say a word to anyone, it was that fierce.
"If I had come across a phone box, I would have got in it and just called my mum."
He spent 18 and a half hours tackling the 185 miles from Paris to Calais.
Bishop's "week of hell" has already raised more than £280,000 for the BT Sport Relief Challenge. The rowing leg was the stretch the comedian had been dreading and the rough seas mean it could take up to nine hours, rather than the hoped-for six, to reach Dover.
Davina said: "John Bishop needs your love and support. He's a broken man, but still positive. It's amazing."
After hitting dry land, Bishop faces three back-to-back marathons taking him to Trafalgar Square in London on Friday. The aim is to raise enough money to vaccinate 250,000 children in Africa, as well as help with projects in the UK.