The 21-year old striker netted a record 59 goals last season, and topping the Northern League scoring charts has seen him rewarded with a move to Championship side Cardiff.
The 59 goals came in just 51 appearances for Guisborough Town, whom the youngster joined following spells with Hartlepool United and Real Murcia.
The former Middlesbrough and Huddersfield target linked up with Ole Gunnar Solskjaer's Bluebirds in pre-season, trialling in their development squad, scoring an impressive goal in a 4-1 loss to Europa League opposition FK Sarajevo.
His performances in pre-season were impressive enough for Solskjaer to take a risk on the youngster, but, with the presence of a host of striking talent ahead of him, it is unlikely that much will be seen of Johnson this season.
However, the striker's former boss Chris Hardy has backed Johnson to make the enormous step up from non-league to Championship football.
Quoted on the official website of the FA, the Guisborough boss said: "Danny will score goals anywhere. He can score from unexpected positions and can find little openings in the bottom corner from the edge of the box.
“It gives me a lot of pleasure to see one of our players sign with a club of Cardiff’s stature.”
A number of other strikers have made the step from non-league and have gone on to impress in not only the second tier, but also the Premier League. Ian Wright, Stan Collymore and John Barnes all represented non-league sides before reaching the top flight, whilst current Manchester United defender Chris Smalling used to turn out for Maidstone United. If Johnson can have the same impact that these legends did, Cardiff may have just uncovered the next footballing gem.